This invention relates to internal combustion engines of the general type used to power vehicles and, more particularly, to a simplified compact modular engine with high reliability that can be produced at a low cost, and to components useful for such a modular engine as well as for other engine configurations.
Automotive design and engineering will always be about options and evolution, particularly in the areas of reducing production costs and increasing fuel efficiency. The internal combustion engine is the dominant mode of power for transport in the modem world. As such, it is necessary that automotive innovators continue to improve their efficiency while reducing the cost of their production and maintenance in the interest of having a positive impact on the environment as well as the global economy.
It is the objective of the present invention to provide a modular internal combustion engine with high reliability that can be manufactured, maintained and repaired at a lower cost than conventional engines.
The present invention provides a modular internal combustion engine (ICE) assembly that includes modular components which allows for the manufacture, maintenance and repair of the present modular engine or other internal combustion engines at a lower cost.
In a preferred embodiment of the modular internal combustion engine, the assembly comprises at least one closed-dome cylinder liner, a cylinder block disposed with at least one cylinder bore adapted to receive the cylinder liner, a modular crankshaft and a plurality of bushings disposed at the lower end of the cylinder block that are adapted to support the modular crankshaft.
The closed-dome cylinder liner includes intake and exhaust valves disposed in the closed-dome portion of the cylinder liner. Preferably, these valves are solenoid actuated whereby the operation of each solenoid is handled by an engine control module. The liner is formed of an inner metallic sleeve sheathed in an aluminum casing. The inner metallic sleeve material provides the necessary porosity to fully lubricate a reciprocating piston during operation. The aluminum sheath has a shoulder portion formed adjacent the dome portion of the liner such that the dome extends above the shoulder. The shoulder portion allows the cylinder to nest on top of the cylinder block such that the shoulder and dome portion of the cylinder liner remains visible while an elongated lower portion of the liner is recessed within a cylinder bore formed in the block. To facilitate the combustion process, the dome portion of the cylinder liner is adapted to threadably receive a spark plug for the purpose of providing an ignition source to the combustion chamber and the cylinder liner is also adapted to communicate with the engine intake and exhaust manifolds as well as the fuel injection system.
As described above, the cylinder block is disposed with at least one cylinder bore adapted to receive the cylinder liner such that the shoulder portion of the liner rests on top of the cylinder block. The cylinder is fixedly mounted in place through an appropriate means known to those skilled in the art. Preferably, the cylinder bores are arranged in a staggered configuration such that the overall engine envelope is minimized.
A plurality of bushings disposed at the lower end of the cylinder block are dimensioned to support an improved crankshaft to be described hereinafter. These bushings provide a bearing and support surface within which the crankshaft rotates in response to a piston power stroke.
The improved crankshaft of the engine assembly comprises a series of discs joined together in spaced parallel relationship by a plurality of crankpins. An end disc of the crankshaft is disposed with an output shaft extending outwardly along a central axis of the crankshaft as a means of delivering mechanical power generated by the engine to peripheral components, such as gears and/or pulleys. The crankpins that connect the discs together in a spaced relationship are adapted to be connected to piston connecting rods in a journal fashion. The crankpins of the present invention serve a dual purpose as crankshaft throws and crankshaft supports commonly used in conventional crankshafts. Thus, the need for having crankshaft supports as required in conventional crankshafts is eliminated and the crankshaft""s length is effectively reduced while its strength is increased.
The discs of the crankshaft are designed to have a high moment of inertia and are of an appropriate size and weight to minimize crankshaft stutter that is caused by a piston power stroke during operation. Preferably, the moment of inertia, size and weight of the discs used to construct the modular crankshaft of the present invention are such that the need for requiring a conventional flywheel is eliminated. Each disc has a circumference that is adapted to be received into the inner diameter of a bushing disposed at the lower end of the engine in a journalled fashion. As mentioned above, the bushings provide a bearing surface for the circumference of the disc much like the main bearings do for the crankshaft in a conventional engine. In response to a piston power stroke, the crankshaft rotatably moves within the bushings. The circumference of each disc may be coated with a wear-resistant material, or alternatively the bushings may provide an antifriction arrangement such as a roller or ball bearings. From the foregoing, a modular internal combustion engine may be constructed that allows for the engine envelope to be downsized without sacrificing engine output.